Commentators have gotten perplexed about James 1:1, where he writes to the twelve tribes which are scattered abroad...
Most conclude that James, being with Peter an apostle of the circumcision (Gal 2:8), was therefore specifically writing to the converted Jews. Those of Jewish descent, children of Abraham as pertains to the flesh. (Romans 4:1)
But in the midst of their deliberation, they ask this one question, "what exactly did James mean..." And this is a great error in reading and interpreting Scripture.
It does not matter what James, or any other apostle or prophet, meant by what they were saying and writing. The only 2 things that really matter is that they accurately said and wrote what God said, what thus saith the Lord, and then what God meant by it.
Nothing in Scripture tells us that the prophetic or apostolic writer must understand what they are talking about, when giving us Scripture inspired of the Holy Spirit. The only mandate is that they give us Scripture from God, not ideas, rules, commandments, ideology, theology from themselves. Or as Moses put it, from his own mind. (Number 16: 28)
In fact, we are told by Scripture that many prophets did not know what they were talking about, when they told us what God said. Daniel is plainly such a case. As well as Scripture telling us that ALL the prophets were searching and wondering about the grace the spoke of, that would be offered to us in Jesus Christ. (1 Peter 1)
And so, the real question is what did God mean by it. James may indeed have even thought he was specifically speaking to his kinsmen according to the flesh (Rom 9:3), that believe, but that doesnt matter to God, nor to us.
And so far as God is concerned, there is no difference between Greek nor Jew, nor any other person in the faith of Jesus. We are ALL believers of one body, neither Jew nor Greek nor male nor female. While there are places in Scripture where God says he is talking specifically to a woman or a man, or a wife, or a husband, nowhere in Scripture does God make it known in the New Covenant and body of Christ, that He is speaking exclusively to certain carnal bloodline or culture. He may be speaking about them, but not exclusively TO them.
And so, a simple conclusion is that God is now calling His churches the 12 tribes, His 12 tribes. We are the New Covenant tribes of Israel. We are the new church and body, the new peculiar people, the new holy nation and priesthood of God (1 Peter 2:9). We are the new creatures and citizens of the commonwealth of Israel (Eph 2:12). The Jews after the flesh who abide in unbelief continue as the new aliens, alienated from god without hope in the world. If they believe, then they are grafted back in with us. Equally. Completely. In unity with distinction nor respect of heritage of flesh.
Even as the everlasting covenant and priesthood of the Old Covenant with the children of Israel has been done away (Heb 8:13, 7:11) and replaced with the New, so have the children of Israel been replaced with the new men (Eph 2:15) (and women) in Christ Jesus.
What was intended to be everlasting ceased to be so, when the Son of God died on the cross, and so likewise did the body of Israel in the flesh die to the covenants and promises and family...and tribes of God, which is now new-born, or born again, with us in Christ Jesus. We are the new Israel of God, and so are we His tribes.
God is the One calling us the 12 tribes in James 1:1, even if James didnt understand it as such. We have Scriptures to prove this, that James was not privy to when he wrote the epistle...of God.
And so, the 12 tribes of Israel of God in Rev 7 are Christians of the New Covenant, whether Jewish or Greekish...